From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Power curves for a ground-boosted RR.F.XI engine.
| Identifier | ExFiles\Box 36\2\ scan 163 | |
| Date | 16th March 1928 | |
| R.R. 493 (40 H) (SL 42 12-7-23). J.H., D.{John DeLooze - Company Secretary} 42934 EXPERIMENTAL REPORT. 16.3.28 COPIES TO R.C.J. B.J. WOR.{Arthur Wormald - General Works Manager} By.{R.W. Bailey - Chief Engineer} E.{Mr Elliott - Chief Engineer} Da.{Bernard Day - Chassis Design} EP.{G. Eric Platford - Chief Quality Engineer} PN.{Mr Northey} OY. (RG{Mr Rowledge}) Expl. No. 4550 REF. Hs{Lord Ernest Hives - Chair}/VH1/LG19.3.28. OBJECT OF TEST. POWER CURVES ON GROUND BOOSTED RR.F.XI. ENGINE. TESTER. V.{VIENNA} Halliwell. CONDITIONS. Engine. RR.F.XI. No.25 (.632/1 gear ratio). Supercharger to LOP. E.31287. (A) S/C gear ratio 5.5/1. (B) S/C gear ratio 6.9/1 Engine compression ratio 6.2/1. Fuel 20/80 Benzol/Aviation. SUMMARY OF TEST. We give herewith power curves for a ground boosted Falcon engine when fitted with two different S/C gear ratios. By fitting the 6.9/1 gear in place of the 5.5/1 gear, the power at 2250 r.p.m. has been increased from 454 HP. to 592 HP. corresponding to an increase in BMEP. of from 148.5 lbs/sq.in. to 161.5 lbs/sq.in. It is noteworthy that these curves were taken on 20/80 benzol/aviation mixture, without any troubles arising due to pre-ignition - Lodge A.30 and KLG.541 plugs were used - each type of plug being fitted to one block of cyls. The highest BMEP. figure recorded on 20/80 benzol mixture with the altitude blower was 155.5 lbs/sq.in. Higher maximum BMEP's are anticipated with a ground boosted engine owing to the lower mixture pipe temp. and reduced HP. contd :- | ||